title: Epitope scanning indicates structural differences in brain-derived monomeric and aggregated mutant prion proteins related to genetic prion diseases.
abstract: Genetic Creutzfeldt-Jakob disease, Gerstmann-Sträussler-Scheinker syndrome, fatal familial insomnia and prion protein cerebral amyloid angiopathy are clinically and neuropathologically distinct neurodegenerative diseases linked to mutations in the PRNP gene encoding the cellular prion protein (PrPC). How sequence variants of PRNP encode the information to specify these disease phenotypes is not known. It is suggested that each mutation produces a misfolded variant of PrPC with specific neurotoxic properties. However, structural studies of recombinant PrP did not detect major differences between wild-type and mutant molecules, pointing to the importance of investigating mutant PrPs from mammalian brains. We used surface plasmon resonance and a slot-blot immunoassay to analyse the antibody-binding profiles of soluble and insoluble PrP molecules extracted from the brains of transgenic mice modelling different prion diseases. By measuring the reactivity of monoclonal antibodies against different PrP epitopes, we obtained evidence of conformational differences between wild-type and mutant PrPs, and among different mutants. We detected structural heterogeneity in both monomeric and aggregated PrP, supporting the hypothesis that the phenotype of genetic prion diseases is encoded by mutant PrP conformation and assembly state.
authors.affiliation: Dulbecco Telethon Institute c/o Department of Neuroscience, IRCCS-Istituto di Ricerche Farmacologiche Mario Negri, Milano 20156, Italy.
authors.forename: Laura
authors.initials: L
authors.lastname: Tapella
authors.forename: Matteo
authors.initials: M
authors.lastname: Stravalaci
authors.forename: Antonio
authors.initials: A
authors.lastname: Bastone
authors.forename: Emiliano
authors.initials: E
authors.lastname: Biasini
authors.forename: Marco
authors.initials: M
authors.lastname: Gobbi
authors.forename: Roberto
authors.initials: R
authors.lastname: Chiesa
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000737:chemistry; D001921:Brain / Q000378:metabolism*; D007562:Creutzfeldt-Jakob Syndrome / Q000235:genetics / Q000378:metabolism*; D003902:Detergents / Q000737:chemistry; D018604:Epitope Mapping; D016098:Gerstmann-Straussler-Scheinker Disease / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D051379:Mice; D008810:Mice, Inbred C57BL; D008808:Mice, Inbred CBA; D008822:Mice, Transgenic; D020125:Mutation, Missense; D011110:Polymorphism, Genetic; D011328:Prions / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D011485:Protein Binding; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D012967:Sodium Dodecyl Sulfate / Q000737:chemistry; D020349:Surface Plasmon Resonance
chemical_list: D000911:Antibodies, Monoclonal; D003902:Detergents; D011328:Prions; D012967:Sodium Dodecyl Sulfate